Trial Information
Status:
Open
Specialty:
Prostate
Date Opened:
26/02/2026
Planned Close date:
21/07/2027
Sponsors:
Janssen Cilag International NV
Site Recruitment:
1 /
5
Principal Investigator:
Dr Omi Parikh
Study Title:
PASenger
Contacts
Research Nurse / Study Coordinator:
Catherine Walmsley
Administrator:
Aaisha Khan
A Phase 3 Randomized, Open-label Study of JNJ-78278343, a T Cell-redirecting agent targeting Human Kallikrein 2, with Docetaxel Versus Docetaxel for Metastatic Castration-Resistant Prostate Cancer
Metastatic castrate-resistant prostate cancer (mCRPC) is a cancer that forms in tissues of male reproductive gland found below the bladder (prostate) and keeps growing despite low levels of male hormones. Although treatment options are available, mCRPC cannot be cured and still causes serious health problems and can lead to death. Pasritamig (JNJ-78278343) is a bispecific antibody* that targets human kallikrein 2 protein on tumour cells and cluster of differentiation 3 protein on T-cells (key cell of immune system). This activates T-cells, which damage tumour cells and stop them from growing.
*protein that recognizes and attaches to 2 different targets.
Docetaxel is a standard of care (widely accepted) treatment option for advanced prostate cancer**.
**cancer that has spread to other parts of body.
In this study, researchers want to assess whether combination treatment of pasritamig and docetaxel prolongs radiographic Progression-Free Survival (rPFS) when compared to treatment with docetaxel alone.
The study consists of:
1.Screening phase (up to 28 days)
2.Treatment phase (up to last dose of study treatment): Participants will be randomly (by chance) assigned to either of the following arms:
a. Pasritamig and Docetaxel
b. Docetaxel
3.End of trial (EOT) visit (within 42 days of last dose of study drug or start of next anticancer therapy)
4.Follow-up phase:
a. Post-treatment follow-up (every 6 weeks): For participants whose disease has not worsened after the treatment or who have not started any next anticancer therapy.
b. Survival follow-up (every 12 weeks until death, loss to follow-up, or study withdrawal, whichever occurs first): For participants whose disease has worsened after the treatment.
Safety assessments include physical examinations, vital signs, adverse events and laboratory assessments. The overall duration of the study is around 3 years 5 months.
All potential participants must satisfy all the following inclusion criteria to be enrolled into thestudy. Participants must:
Age
1. Be ≥18 years of age at the time of informed consent or at least the legal age of majority inthe jurisdiction in which the study is taking place
Disease Characteristics
2. Have histologically confirmed adenocarcinoma of the prostate. Participants with primary (ordocumented evidence of conversion to) small cell carcinoma, carcinoid tumor, mixed NE
carcinoma, large cell NE carcinoma, or sarcoma of the prostate are excluded.
3. Have disease that is metastatic at the time of the screening as determined by the investigator.
4. Have progressive disease defined as at least one of the following:
PSA level ≥2 ng/mL that has increased on at least 2 successive occasions at least1 week apart.
Progressive disease or new lesion(s) in the lymph nodes, bones, or viscera as definedby RECIST v1.1 and/or in bone scan per PCWG3 while on medical or surgical castration.
Prior Therapy Restrictions or Requirements
5. Participants must receive ongoing ADT with a GnRH analog (agonist or antagonist) throughout the Treatment Phase or have had prior bilateral orchiectomy, and have serum
testosterone ≤50 ng/dL (≤1.73 nmol/L) at screening.
6. Have progressed on at least 1 novel ARPI but received no more than 2 different ARPI (eg, abiraterone acetate, apalutamide, enzalutamide, darolutamide) for any stage of disease. Must have discontinued ARPI before randomization into the study.
Performance Status
7. Have an ECOG performance status of 0 to 1 (Oken 1982).
Renal Function
8. Have an eGFR, calculated with the CKD-epi formula (at
https://www.kidney.org/professionals/gfr_calculator), of >30 mL/min during the screening period. Participants with obstructive uropathy should have treatment prior to randomization
Hematologic Values
10. Have the following laboratory values during the screening period:
Hemoglobin ≥9.0 g/dL Neutrophils ≥1.5 x 109
/L Platelets ≥100 x 109 /L
Note, transfusion or growth factor usage within 14 days of randomization is not allowed.
Sex and Contraceptive/Barrier Requirements
13. Agree, while on study treatment and for 6 months after the last dose of study treatment, to:
Not donate gametes (ie, sperm) or freeze for future use for the purposes of assisted reproduction.
Wear an external condom, when transmission of sperm/ejaculate can occur.
If able to produce sperm and their partner is of childbearing potential, the partner must practice a highly effective method of contraception.
See Appendix 3: Contraceptive and Barrier Guidance for details.
Informed Consent
14. Participant (or their legally designated representative) must sign an ICF.
15. Be willing and able to adhere to the lifestyle restrictions specified in this protocol.
Age
1. Be ≥18 years of age at the time of informed consent or at least the legal age of majority inthe jurisdiction in which the study is taking place
Disease Characteristics
2. Have histologically confirmed adenocarcinoma of the prostate. Participants with primary (ordocumented evidence of conversion to) small cell carcinoma, carcinoid tumor, mixed NE
carcinoma, large cell NE carcinoma, or sarcoma of the prostate are excluded.
3. Have disease that is metastatic at the time of the screening as determined by the investigator.
4. Have progressive disease defined as at least one of the following:
PSA level ≥2 ng/mL that has increased on at least 2 successive occasions at least1 week apart.
Progressive disease or new lesion(s) in the lymph nodes, bones, or viscera as definedby RECIST v1.1 and/or in bone scan per PCWG3 while on medical or surgical castration.
Prior Therapy Restrictions or Requirements
5. Participants must receive ongoing ADT with a GnRH analog (agonist or antagonist) throughout the Treatment Phase or have had prior bilateral orchiectomy, and have serum
testosterone ≤50 ng/dL (≤1.73 nmol/L) at screening.
6. Have progressed on at least 1 novel ARPI but received no more than 2 different ARPI (eg, abiraterone acetate, apalutamide, enzalutamide, darolutamide) for any stage of disease. Must have discontinued ARPI before randomization into the study.
Performance Status
7. Have an ECOG performance status of 0 to 1 (Oken 1982).
Renal Function
8. Have an eGFR, calculated with the CKD-epi formula (at
https://www.kidney.org/professionals/gfr_calculator), of >30 mL/min during the screening period. Participants with obstructive uropathy should have treatment prior to randomization
Hematologic Values
10. Have the following laboratory values during the screening period:
Hemoglobin ≥9.0 g/dL Neutrophils ≥1.5 x 109
/L Platelets ≥100 x 109 /L
Note, transfusion or growth factor usage within 14 days of randomization is not allowed.
Sex and Contraceptive/Barrier Requirements
13. Agree, while on study treatment and for 6 months after the last dose of study treatment, to:
Not donate gametes (ie, sperm) or freeze for future use for the purposes of assisted reproduction.
Wear an external condom, when transmission of sperm/ejaculate can occur.
If able to produce sperm and their partner is of childbearing potential, the partner must practice a highly effective method of contraception.
See Appendix 3: Contraceptive and Barrier Guidance for details.
Informed Consent
14. Participant (or their legally designated representative) must sign an ICF.
15. Be willing and able to adhere to the lifestyle restrictions specified in this protocol.
Any potential participant who meets any of the following exclusion criteria will be excluded from participating in the study.
Medical Conditions
1. Known history of either brain or leptomeningeal prostate cancer metastases.
2. Patients with known BRCA 1/2 mutations (germline or somatic) who have not received treatment with a PARP inhibitor, unless not available or contraindicated.
3. Suspected or known allergies, hypersensitivity, or intolerance to pasritamig excipients (refer to the pasritamig IB and Addenda) or docetaxel excipients (Taxotere PI).
4. Not recovered from recent surgery.
5. Solid organ or bone marrow transplantation.
6. Active autoimmune disease within the 12 months prior to signing consent that requires systemic immunosuppressive medications (eg, chronic corticosteroid, methotrexate
or tacrolimus).
Cardiovascular Dysfunction
7. Any of the following within 6 months prior to first dose of study treatment: severe or unstable angina,
myocardial infarction, major thromboembolic events (eg, pulmonary embolism, cerebrovascular accident),
clinically significant ventricular arrhythmias or heart failure New York Heart Association functional classification Class II to IV.
Note: Uncomplicated deep vein thrombosis is not considered exclusionary.
Prior Malignancies
8. Prior or concurrent second malignancy (other than the disease under study) because the natural history or treatment could interfere with study endpoints (see Appendix 5
on Allowed Recent Second or Prior Malignancies for details).
Disease Characteristics
9. Received cytotoxic chemotherapy for prostate cancer in any setting (eg, docetaxel, cabazitaxel, mitoxantrone, etc).
10. Received prior treatment with KLK-2-directed therapies.
11. Received prior treatment for prostate cancer with:
CD3 redirector therapies or
Radiopharmaceutical agents or
Immunotherapy agents for prostate cancer (eg, sipuleucel-T, PD-1 inhibitors,
T-cell redirectors, costimulatory agents, etc) or PARP inhibitors (other than for BRCA1/2 mutation) or
Any other investigational agent for the treatment of mCRPC.
HIV Status
12. Participants who are HIV-positive and meet any of the following:
a) Detectable viral load (ie, >50 copies/mL) at screening.
b) CD4+ count <300 cells/mm3 at screening.
c) AIDS-defining opportunistic infection within 6 months of screening.
d) Receive treatment other than continued HAART. A change in HAART due to resistance/progression must occur at least 3 months prior to screening. A change in HAART due to toxicity is allowed up to 4 weeks prior to screening.
Note: HAART that could interfere with study treatment is excluded (consult the Sponsor for a review of medications prior to enrollment)
Viral Hepatitis Assessments
13. Active hepatitis of infectious origin.
a) Seropositive for hepatitis B: defined by a positive test for HBsAg. Participants
with resolved infection (ie, participants who are HBsAg negative with positive antibodies to total hepatitis B core antigen [anti-HBc]) must be screened using RT-PCR measurement of HBV DNA levels. Those who are RT-PCR positive will be excluded. Participants with serologic findings suggestive of HBV
vaccination (anti-HBs positivity as the only serologic marker) AND a known history of prior HBV vaccination, do not need to be tested for HBV DNA by RT-PCR (see Appendix 6).
b) Known hepatitis C infection or positive serologic testing for hepatitis C virus (anti-HCV) antibody.
Participants with positive hepatitis C antibody due to prior resolved disease can be enrolled only if a confirmatory negative hepatitis C RNA test is obtained at screening or within 3 months prior to first dose of study treatment.
c) Other clinically active liver disease of infectious origin.
Prior/Concomitant Therapy or Clinical Study Experience
14. Received or plans to receive any live, attenuated vaccine within 4 weeks before the first dose of study treatment. Non-live and non-replication-competent vaccines are
allowed.
15. Received systemic glucocorticoids (doses >10 mg/day prednisone or equivalent)
within 3 days prior to the first dose of study treatment. A single course of glucocorticoids is permitted as prophylaxis for imaging contrast (ie, for participants with allergies to contrast). If glucocorticoids were used to treat immune-related
adverse events associated with prior therapy, ≥7 days must have elapsed since the last dose of corticosteroid.
16. Received external beam radiation therapy within 14 days prior to start of study treatment. However, if palliative focal radiation was used, the participant is eligible regardless of date of radiation
Medical Conditions
1. Known history of either brain or leptomeningeal prostate cancer metastases.
2. Patients with known BRCA 1/2 mutations (germline or somatic) who have not received treatment with a PARP inhibitor, unless not available or contraindicated.
3. Suspected or known allergies, hypersensitivity, or intolerance to pasritamig excipients (refer to the pasritamig IB and Addenda) or docetaxel excipients (Taxotere PI).
4. Not recovered from recent surgery.
5. Solid organ or bone marrow transplantation.
6. Active autoimmune disease within the 12 months prior to signing consent that requires systemic immunosuppressive medications (eg, chronic corticosteroid, methotrexate
or tacrolimus).
Cardiovascular Dysfunction
7. Any of the following within 6 months prior to first dose of study treatment: severe or unstable angina,
myocardial infarction, major thromboembolic events (eg, pulmonary embolism, cerebrovascular accident),
clinically significant ventricular arrhythmias or heart failure New York Heart Association functional classification Class II to IV.
Note: Uncomplicated deep vein thrombosis is not considered exclusionary.
Prior Malignancies
8. Prior or concurrent second malignancy (other than the disease under study) because the natural history or treatment could interfere with study endpoints (see Appendix 5
on Allowed Recent Second or Prior Malignancies for details).
Disease Characteristics
9. Received cytotoxic chemotherapy for prostate cancer in any setting (eg, docetaxel, cabazitaxel, mitoxantrone, etc).
10. Received prior treatment with KLK-2-directed therapies.
11. Received prior treatment for prostate cancer with:
CD3 redirector therapies or
Radiopharmaceutical agents or
Immunotherapy agents for prostate cancer (eg, sipuleucel-T, PD-1 inhibitors,
T-cell redirectors, costimulatory agents, etc) or PARP inhibitors (other than for BRCA1/2 mutation) or
Any other investigational agent for the treatment of mCRPC.
HIV Status
12. Participants who are HIV-positive and meet any of the following:
a) Detectable viral load (ie, >50 copies/mL) at screening.
b) CD4+ count <300 cells/mm3 at screening.
c) AIDS-defining opportunistic infection within 6 months of screening.
d) Receive treatment other than continued HAART. A change in HAART due to resistance/progression must occur at least 3 months prior to screening. A change in HAART due to toxicity is allowed up to 4 weeks prior to screening.
Note: HAART that could interfere with study treatment is excluded (consult the Sponsor for a review of medications prior to enrollment)
Viral Hepatitis Assessments
13. Active hepatitis of infectious origin.
a) Seropositive for hepatitis B: defined by a positive test for HBsAg. Participants
with resolved infection (ie, participants who are HBsAg negative with positive antibodies to total hepatitis B core antigen [anti-HBc]) must be screened using RT-PCR measurement of HBV DNA levels. Those who are RT-PCR positive will be excluded. Participants with serologic findings suggestive of HBV
vaccination (anti-HBs positivity as the only serologic marker) AND a known history of prior HBV vaccination, do not need to be tested for HBV DNA by RT-PCR (see Appendix 6).
b) Known hepatitis C infection or positive serologic testing for hepatitis C virus (anti-HCV) antibody.
Participants with positive hepatitis C antibody due to prior resolved disease can be enrolled only if a confirmatory negative hepatitis C RNA test is obtained at screening or within 3 months prior to first dose of study treatment.
c) Other clinically active liver disease of infectious origin.
Prior/Concomitant Therapy or Clinical Study Experience
14. Received or plans to receive any live, attenuated vaccine within 4 weeks before the first dose of study treatment. Non-live and non-replication-competent vaccines are
allowed.
15. Received systemic glucocorticoids (doses >10 mg/day prednisone or equivalent)
within 3 days prior to the first dose of study treatment. A single course of glucocorticoids is permitted as prophylaxis for imaging contrast (ie, for participants with allergies to contrast). If glucocorticoids were used to treat immune-related
adverse events associated with prior therapy, ≥7 days must have elapsed since the last dose of corticosteroid.
16. Received external beam radiation therapy within 14 days prior to start of study treatment. However, if palliative focal radiation was used, the participant is eligible regardless of date of radiation